Buying or Selling? Test for Radon!

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Are you buying or selling a home or do you work with people who are? Congratulations! Buying a new home is an important occasion and the perfect time to test for radon. Radon is a naturally occurring, odorless, colorless, radioactive gas that is found in Wisconsin homes. Behind smoking, radon is the second leading cause of lung cancer in the United States. 

While radon testing is not required by law or regulated in Wisconsin, we recommend testing for radon during real estate transactions to better understand radon levels and lung cancer risk. Luckily, testing a home for radon is easy and can put both the buyer’s and seller’s mind at ease. If a radon test is conducted, it should be done in the basement or lowest livable level of the home. Typically, the year average of radon levels in basements is double the radon levels on the main floors of homes where residents spend most of their time. Thus, long-term, year-long measurements provide a more accurate estimate of radon exposure and lung cancer risks. However, we recognize the time constraints of real-estate transactions, and recommend that at least two-day, closed condition radon tests are conducted.

Certified individuals in a Radon Proficiency Program for Residential Measurement should be used for radon testing in real estate transfers. In Wisconsin, the seller must inform the buyer of any known unsafe levels of radon. The U.S. EPA recommends mitigating (fixing) radon at levels of 4 pico Curies per Liter (pCi/L) or greater. Fixing or mitigating a radon problem usually isn’t hard! While both home buyers and sellers in Wisconsin are free to negotiate and respond as they choose, it is ultimately up to the buyer to decide what is an acceptable level of radon risk in the home

To learn more, check out these resources:

  • Our Home Buyers Radon Brochure (PDF, 309 KB) provides recommendations for radon testing for buyers, sellers, and real estate professionals.
  • The U.S. EPA's Radon Mitigation System Checklist (PDF, 41 KB) is for home buyers of homes already having radon control systems in place. The checklist can also be used to verify the components of a proposed radon control system.
  • A short video for home inspectors and realtors describes how to deal with radon in real estate transactions.
Last Revised: August 3, 2017